Air conditioning apparatus



' dissipated by the United States Patent cc Patented Apr. 12,

2,932,178 AIR CONDITIONING APPARATUS Application November 25, 1958, Serial No. 776,296

' 6 Claims. (Cl. 62-324) This invention relates to air conditioning apparatus and more particularly to a compression refrigeration air conditioning unit adapted for regulation of humidity content of the conditioned air. 7

In maintaining air conditions within an enclosure that are comfortable to humans, it is necessary that the moisture content of the air, as well as the air temperature, be controlled. High air temperature is generally accompanied by high humidity and both conditions can be corrected, or rendered satisfacto by passing the air through an air cooling unit, because dehumidi fication to an acceptable level generally accompaniescooling. There are, however, periods during which the air temperature is at an acceptable level but the air nevertheless contains a high percentage of moisture, so that discomfort is experienced. Under these conditions dehumidification, unaccompanied by reduction of the sensible heat in the air, is desirable. V

This invention relates to a refrigerating system or circuit, the. operation of which can be alteredor modified to effect substantially pure dehumidification of air, i.e. dehumdification without reduction of the sensible heat in the conditioned air. Moreover, this invention requires only simple additions to and changes in a refrigerating system and, consequently, air conditioning units, such as those employed to con.- dition one or more rooms in a private residence.

In accordance with this invention, both the indoor air and outdoor air portions of the air conditioning unit are equipped with two heat exchangers. A single compressor, generally disposed in the outdoor air portion of the unit, is employed to circulate, or pump, refrigerant fluid through these several heat exchangers. One'indoor heat exchanger and one outdoor heat exchanger are connected' to the compressor by means including a refrigerant flow reversing device which selectively directs refrigerant through the outdoor heat exchanger to the indoor heat exchanger or through the indoor heat exchanger to the outdoor heat exchanger, whereby heat is selectively absorbed by one of saidheat exchangers and other of said heat exchangers. This enables this indoor heat exchanger tooperate either as an evaporator, for cooling indoor air or as a condenser for heating indoor air. I a 5, a

Further, in accordance with the invention, the other two heat exchangers, i.e., the other indoor heat exchanger and the other outdoor heatexchanger, are connected to the compressor in parallel refrigerant flow relationship to the two reversible heat exchangers that said other indoor heat exchanger always functions as an evaporator to cool indoor air,-and said other outdoor heat exchanger always functions as a condenser to dissipate heat to outdoor air.

The object of connecting the several heat exchangers in the aforesaid manner is to enable bothindoor heat e x, changers to function as evaporators for the purpose of cooling indoor air'when high temperature conditions, either with or without high humidity, are encountered,

may be utilized in low cost and further, to enable one indoor heat exchanger to function as a condenser for reheating air that hasbeen cooled; and dehumidified by the other indoor heat exchanger, so that the indoor air is dehumidified without sensible cooling when only high humidity conditions are encountered. The several features, objects and advantages of the invention are'elucidated in the following detailed description of which the'accompany drawing forms a part and wherein: p a Fig. 1 is a simplified illustration of an air conditioning unit embodying this invention;

Fig. 2 is a schematic refrigerant circuit diagram of a refrigeration system embodying the invention; and Fig. 3 is another diagram of the refrigeration system showing a different operating condition thereof. 1 The air conditioning unit embodying the invention includes a casing 11, having a' partition 12 therein that divides the unit into an indoor section 13 and an outdoor section 14. The casing 11 is adapted to be mounted within an opening, such as a window, of a building wall 15 in such a manner that the indoor section, 13, com-.

municates with air to be conditioned in other enclosure. The outdoor section, 14, communicates with outdoor air, i.e. air outside the conditioned enclosure. The indoor section 13 contains first and second heat exchangers 16 and 17 which are arranged in facing relationship adjacent one another. Air to be conditioned enters the indoor section of the unit through an inlet opening 18 and is circulated by air propelling means, such as a motor driven propeller fan 19, over, or through, first indoor heat exchanger 16 and then indoor heat exchanger 17, and is returned to the conditioned enclosure through an outlet 20. Moisture that is condensed from the air as a result of cooling falls into a collection trough 21 and is conveyed from the conditioned enclosure by suitable drain means (not shown).

Heat is absorbed from and/or dissipated to the outdoor air by first and second outdoor heat exchangers 22 and 23 located within outdoor, air section 14 of the unit. These heat exchangers are also preferably disposed in face-to-face relationship adjacent one another. Outdoor air is circulated over heat exchangers 22 and 23 by suit-- able air propelling means, such as a motor driven propeller fan 24. a

The several heat exchangers form part of a compres sion refrigeration system, which includes 'a compressor 25 preferably located in the outdoor section of the unit." The compressor 25, in accordance with conventional practice, is preferably enclosed within a sealed casing which also'houses the motor for driving the compressor. As

a room or best shown in Fig. 2, the compressor 25 includesconduit' pressor.

in such a manner The compressor 25 is adapted to pump, refrigerant fluid through two parallel refrigerant flow paths, each of which paths includes one indoor heat ex-f changer and one outdoor heat exchanger. The first flow path is conventional, in that a discharge conduit 28 conveys refrigerant from the compressor outlet 27 tothe first outdoor heat exchanger 22, wherein heat is trans ferred to the outdoor air and refrigerant is condensedL The outdoor heat exchanger 22 is connected to the first indoor heat exchanger 16 by conduit means including a small bore restrictor tube 29. The pressure of the refrigerant flowing through tube 29 is progressively reduced and the refrigerant is thereafter evaporated at low pres-- sure in the indoor heat exchanger 16 to absorb heat from indoor air. Vaporous refrigerant is returned from heat via a suction conduit 30. 7 Outdoor heat exchanger 22 functions as a exchanger 16 to the compressor inlet 26 condenser and indoor heat exchanger 16 functions as an evaporator in this first refrigerant flow path.

or convey,-

providing a second refrigerant flow path parallel to said first refrigerant flow path and adapted to selectively direct refrigerant from said compressor through said second outdoor heat exchanger to said second indoor heat exchanger or through said second indoor heat exchanger to said second outdoor heat exchanger, whereby heat is selectively absorbed in one of said second heat exchangers and dissipated by the other of said second heat exchangers.

2. In air conditioning apparatus including a compression refrigeration system, a compressor, an indoor heat exchanger, an evaporator, means for directing air to be conditioned first over said evaporator and then over said indoor heat exchanger, a condenser, an outdoor heat exchanger, means for directing outside air first over said condenser and then over said outdoor heat exchanger, conduit means for routing refrigerant from said compressor through said condenser to said evaporator and back to said compressor, and means including a reversing valve for selectively routing refrigerant from said compressor through said outdoor heat exchanger to said indoor heat exchanger or through said indoor heat exchanger to said outdoor heat exchanger, whereby said indoor heat exchanger can be connected in parallel refrigerant flow relationship with either said evaporator or said condenser.

3. In air conditioning apparatus including a compression refrigeration system, a compressor, an indoor heat exchanger, an evaporator arranged in face-to-face relationship with said indoor heat exchanger, means for directing air to be conditioned first over said evaporator and then over said indoor heat exchanger, a condenser, an outdoor heat exchanger arranged in face-to-face relationship with said condenser, means for directing outside air first over said condenser and then over said outdoor heat exchanger, conduit means for routing refrigerant from said compressor through said condenser to said evaporator and back to said compressor, and means including a reversing valve for selectively routing refrigerant from said compressor through said outdoor heat exchanger to said indoor heat exchanger or through said indoor heat exchanger to said outdoor heat exchanger, whereby said indoor heat exchanger can be connected in parallel refrigerant flow relationship with either said evaporator or said condenser.

4. In air conditioning apparatus including a compression refrigeration system, a compressor having an inlet and an outlet, an indoor heat exchanger, an outdoor heat exchanger, means including a bidirectional expansion device connecting said outdoor heat exchanger to said indoor heat exchanger and permitting refrigerant flow in either direction from one to the other of said heat exchangers, means including a reversing valve for selectively connecting the outlet of said compressor to said outdoor heat exchanger and the inlet of said compressor to said indoor heat exchanger or the outlet of said compressor to said indoor heat exchanger and the inlet of said compressor to said outdoor heat exchanger, an evaporator, a. concirculating indoor air over said indoor heat exchanger and said evaporator, and means for circulating outdoor air over said outdoor heat exchanger and said condenser.

5. In air conditioning apparatus including a compression refrigeration system, a compressor having an inlet and an outlet, an indoor heat exchanger, an outdoor heat exchanger, means including a bidirectional expansion device connecting said outdoor heat exchanger to said indoor heat exchanger and permitting refrigerant flow in either direction from one to the other of said heat exchangers, means including a reversing valve for selectively connecting the outlet of said compressor to said outdoor heat exchanger and the inlet of said compressor to said indoor heat exchanger or the outlet of said compressor to said indoor heat exchanger and the inlet of said compressor to said outdoor heat exchanger, an evaporator disposed adjacent said indoor heat exchanger, a condenser disposed adjacent said outdoor heat exchanger, means connecting said compressor, condenser, and evaporator for routing refrigerant from said compressor through said condenser to said evaporator regardless of the condition of said reversing valve, means for circulating indoor air first over said evaporator and then over said indoor heat exchanger, and means for circulating outdoor air first over said condenser and then over said outdoor heat exchanger.

6. In a refrigeration circuit for air conditioning apparatus, a compressor having an inlet and an outlet, first and second indoor heat exchangers, first and second outdoor heat exchangers, means including an expansion device connecting the first outdoor heat exchanger to the first indoor heat exchanger, conduit means connecting the outlet of said compressor to said first outdoor heat exchanger and the inlet of said compressor to said first indoor heat exchanger, means including a bidirectional expansion device connecting said second outdoor heat exchanger to said second indoor heat exchanger and permitting refrigerant to flow in either direction from one to the other of said second heat exchangers, and means including a reversing valve for selectively connecting the outlet of said compressor to said second outdoor heat exchanger and the inlet of said compressor to said second indoor heat exchanger or the outlet of said compressor to said second indoor heat exchanger and the inlet of the compressor to said second outdoor heat exchanger.

References Cited in the file of this patent UNITED STATES PATENTS 2,241,060 Gibson May 6, 1941 2,619,812 Burgess Dec. 2, 1952 2,785,540 Biehn Mar. 19, 1957 Notice of Adverse Decision in Interference In Interference No. 91,359 involving Patent No. 2,932,17 8, A. Armstrong and M. D. Ulich, Air conditioning apparatus, final decision adverse to the patentees was rendered J an. 30, 1963, as to claims 1 i and 6.

[Ofiicz'al Gazette August 27, 1963.] 

